Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64...

[~andy/linux] / drivers / net / ethernet / intel / e1000e / mac.c

/*******************************************************************************

  Intel PRO/1000 Linux driver
  Copyright(c) 1999 - 2013 Intel Corporation.

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  more details.

  You should have received a copy of the GNU General Public License along with
  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information:
  Linux NICS <linux.nics@intel.com>
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

*******************************************************************************/

#include "e1000.h"

/**
 *  e1000e_get_bus_info_pcie - Get PCIe bus information
 *  @hw: pointer to the HW structure
 *
 *  Determines and stores the system bus information for a particular
 *  network interface.  The following bus information is determined and stored:
 *  bus speed, bus width, type (PCIe), and PCIe function.
 **/
s32 e1000e_get_bus_info_pcie(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        struct e1000_bus_info *bus = &hw->bus;
        struct e1000_adapter *adapter = hw->adapter;
        u16 pcie_link_status, cap_offset;

        cap_offset = adapter->pdev->pcie_cap;
        if (!cap_offset) {
                bus->width = e1000_bus_width_unknown;
        } else {
                pci_read_config_word(adapter->pdev,
                                     cap_offset + PCIE_LINK_STATUS,
                                     &pcie_link_status);
                bus->width = (enum e1000_bus_width)((pcie_link_status &
                                                     PCIE_LINK_WIDTH_MASK) >>
                                                    PCIE_LINK_WIDTH_SHIFT);
        }

        mac->ops.set_lan_id(hw);

        return 0;
}

/**
 *  e1000_set_lan_id_multi_port_pcie - Set LAN id for PCIe multiple port devices
 *
 *  @hw: pointer to the HW structure
 *
 *  Determines the LAN function id by reading memory-mapped registers
 *  and swaps the port value if requested.
 **/
void e1000_set_lan_id_multi_port_pcie(struct e1000_hw *hw)
{
        struct e1000_bus_info *bus = &hw->bus;
        u32 reg;

        /* The status register reports the correct function number
         * for the device regardless of function swap state.
         */
        reg = er32(STATUS);
        bus->func = (reg & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;
}

/**
 *  e1000_set_lan_id_single_port - Set LAN id for a single port device
 *  @hw: pointer to the HW structure
 *
 *  Sets the LAN function id to zero for a single port device.
 **/
void e1000_set_lan_id_single_port(struct e1000_hw *hw)
{
        struct e1000_bus_info *bus = &hw->bus;

        bus->func = 0;
}

/**
 *  e1000_clear_vfta_generic - Clear VLAN filter table
 *  @hw: pointer to the HW structure
 *
 *  Clears the register array which contains the VLAN filter table by
 *  setting all the values to 0.
 **/
void e1000_clear_vfta_generic(struct e1000_hw *hw)
{
        u32 offset;

        for (offset = 0; offset < E1000_VLAN_FILTER_TBL_SIZE; offset++) {
                E1000_WRITE_REG_ARRAY(hw, E1000_VFTA, offset, 0);
                e1e_flush();
        }
}

/**
 *  e1000_write_vfta_generic - Write value to VLAN filter table
 *  @hw: pointer to the HW structure
 *  @offset: register offset in VLAN filter table
 *  @value: register value written to VLAN filter table
 *
 *  Writes value at the given offset in the register array which stores
 *  the VLAN filter table.
 **/
void e1000_write_vfta_generic(struct e1000_hw *hw, u32 offset, u32 value)
{
        E1000_WRITE_REG_ARRAY(hw, E1000_VFTA, offset, value);
        e1e_flush();
}

/**
 *  e1000e_init_rx_addrs - Initialize receive address's
 *  @hw: pointer to the HW structure
 *  @rar_count: receive address registers
 *
 *  Setup the receive address registers by setting the base receive address
 *  register to the devices MAC address and clearing all the other receive
 *  address registers to 0.
 **/
void e1000e_init_rx_addrs(struct e1000_hw *hw, u16 rar_count)
{
        u32 i;
        u8 mac_addr[ETH_ALEN] = { 0 };

        /* Setup the receive address */
        e_dbg("Programming MAC Address into RAR[0]\n");

        hw->mac.ops.rar_set(hw, hw->mac.addr, 0);

        /* Zero out the other (rar_entry_count - 1) receive addresses */
        e_dbg("Clearing RAR[1-%u]\n", rar_count - 1);
        for (i = 1; i < rar_count; i++)
                hw->mac.ops.rar_set(hw, mac_addr, i);
}

/**
 *  e1000_check_alt_mac_addr_generic - Check for alternate MAC addr
 *  @hw: pointer to the HW structure
 *
 *  Checks the nvm for an alternate MAC address.  An alternate MAC address
 *  can be setup by pre-boot software and must be treated like a permanent
 *  address and must override the actual permanent MAC address. If an
 *  alternate MAC address is found it is programmed into RAR0, replacing
 *  the permanent address that was installed into RAR0 by the Si on reset.
 *  This function will return SUCCESS unless it encounters an error while
 *  reading the EEPROM.
 **/
s32 e1000_check_alt_mac_addr_generic(struct e1000_hw *hw)
{
        u32 i;
        s32 ret_val;
        u16 offset, nvm_alt_mac_addr_offset, nvm_data;
        u8 alt_mac_addr[ETH_ALEN];

        ret_val = e1000_read_nvm(hw, NVM_COMPAT, 1, &nvm_data);
        if (ret_val)
                return ret_val;

        /* not supported on 82573 */
        if (hw->mac.type == e1000_82573)
                return 0;

        ret_val = e1000_read_nvm(hw, NVM_ALT_MAC_ADDR_PTR, 1,
                                 &nvm_alt_mac_addr_offset);
        if (ret_val) {
                e_dbg("NVM Read Error\n");
                return ret_val;
        }

        if ((nvm_alt_mac_addr_offset == 0xFFFF) ||
            (nvm_alt_mac_addr_offset == 0x0000))
                /* There is no Alternate MAC Address */
                return 0;

        if (hw->bus.func == E1000_FUNC_1)
                nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN1;
        for (i = 0; i < ETH_ALEN; i += 2) {
                offset = nvm_alt_mac_addr_offset + (i >> 1);
                ret_val = e1000_read_nvm(hw, offset, 1, &nvm_data);
                if (ret_val) {
                        e_dbg("NVM Read Error\n");
                        return ret_val;
                }

                alt_mac_addr[i] = (u8)(nvm_data & 0xFF);
                alt_mac_addr[i + 1] = (u8)(nvm_data >> 8);
        }

        /* if multicast bit is set, the alternate address will not be used */
        if (is_multicast_ether_addr(alt_mac_addr)) {
                e_dbg("Ignoring Alternate Mac Address with MC bit set\n");
                return 0;
        }

        /* We have a valid alternate MAC address, and we want to treat it the
         * same as the normal permanent MAC address stored by the HW into the
         * RAR. Do this by mapping this address into RAR0.
         */
        hw->mac.ops.rar_set(hw, alt_mac_addr, 0);

        return 0;
}

/**
 *  e1000e_rar_set_generic - Set receive address register
 *  @hw: pointer to the HW structure
 *  @addr: pointer to the receive address
 *  @index: receive address array register
 *
 *  Sets the receive address array register at index to the address passed
 *  in by addr.
 **/
void e1000e_rar_set_generic(struct e1000_hw *hw, u8 *addr, u32 index)
{
        u32 rar_low, rar_high;

        /* HW expects these in little endian so we reverse the byte order
         * from network order (big endian) to little endian
         */
        rar_low = ((u32)addr[0] | ((u32)addr[1] << 8) |
                   ((u32)addr[2] << 16) | ((u32)addr[3] << 24));

        rar_high = ((u32)addr[4] | ((u32)addr[5] << 8));

        /* If MAC address zero, no need to set the AV bit */
        if (rar_low || rar_high)
                rar_high |= E1000_RAH_AV;

        /* Some bridges will combine consecutive 32-bit writes into
         * a single burst write, which will malfunction on some parts.
         * The flushes avoid this.
         */
        ew32(RAL(index), rar_low);
        e1e_flush();
        ew32(RAH(index), rar_high);
        e1e_flush();
}

/**
 *  e1000_hash_mc_addr - Generate a multicast hash value
 *  @hw: pointer to the HW structure
 *  @mc_addr: pointer to a multicast address
 *
 *  Generates a multicast address hash value which is used to determine
 *  the multicast filter table array address and new table value.
 **/
static u32 e1000_hash_mc_addr(struct e1000_hw *hw, u8 *mc_addr)
{
        u32 hash_value, hash_mask;
        u8 bit_shift = 0;

        /* Register count multiplied by bits per register */
        hash_mask = (hw->mac.mta_reg_count * 32) - 1;

        /* For a mc_filter_type of 0, bit_shift is the number of left-shifts
         * where 0xFF would still fall within the hash mask.
         */
        while (hash_mask >> bit_shift != 0xFF)
                bit_shift++;

        /* The portion of the address that is used for the hash table
         * is determined by the mc_filter_type setting.
         * The algorithm is such that there is a total of 8 bits of shifting.
         * The bit_shift for a mc_filter_type of 0 represents the number of
         * left-shifts where the MSB of mc_addr[5] would still fall within
         * the hash_mask.  Case 0 does this exactly.  Since there are a total
         * of 8 bits of shifting, then mc_addr[4] will shift right the
         * remaining number of bits. Thus 8 - bit_shift.  The rest of the
         * cases are a variation of this algorithm...essentially raising the
         * number of bits to shift mc_addr[5] left, while still keeping the
         * 8-bit shifting total.
         *
         * For example, given the following Destination MAC Address and an
         * mta register count of 128 (thus a 4096-bit vector and 0xFFF mask),
         * we can see that the bit_shift for case 0 is 4.  These are the hash
         * values resulting from each mc_filter_type...
         * [0] [1] [2] [3] [4] [5]
         * 01  AA  00  12  34  56
         * LSB           MSB
         *
         * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
         * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
         * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
         * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
         */
        switch (hw->mac.mc_filter_type) {
        default:
        case 0:
                break;
        case 1:
                bit_shift += 1;
                break;
        case 2:
                bit_shift += 2;
                break;
        case 3:
                bit_shift += 4;
                break;
        }

        hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
                                   (((u16)mc_addr[5]) << bit_shift)));

        return hash_value;
}

/**
 *  e1000e_update_mc_addr_list_generic - Update Multicast addresses
 *  @hw: pointer to the HW structure
 *  @mc_addr_list: array of multicast addresses to program
 *  @mc_addr_count: number of multicast addresses to program
 *
 *  Updates entire Multicast Table Array.
 *  The caller must have a packed mc_addr_list of multicast addresses.
 **/
void e1000e_update_mc_addr_list_generic(struct e1000_hw *hw,
                                        u8 *mc_addr_list, u32 mc_addr_count)
{
        u32 hash_value, hash_bit, hash_reg;
        int i;

        /* clear mta_shadow */
        memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));

        /* update mta_shadow from mc_addr_list */
        for (i = 0; (u32)i < mc_addr_count; i++) {
                hash_value = e1000_hash_mc_addr(hw, mc_addr_list);

                hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
                hash_bit = hash_value & 0x1F;

                hw->mac.mta_shadow[hash_reg] |= (1 << hash_bit);
                mc_addr_list += (ETH_ALEN);
        }

        /* replace the entire MTA table */
        for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
                E1000_WRITE_REG_ARRAY(hw, E1000_MTA, i, hw->mac.mta_shadow[i]);
        e1e_flush();
}

/**
 *  e1000e_clear_hw_cntrs_base - Clear base hardware counters
 *  @hw: pointer to the HW structure
 *
 *  Clears the base hardware counters by reading the counter registers.
 **/
void e1000e_clear_hw_cntrs_base(struct e1000_hw *hw)
{
        er32(CRCERRS);
        er32(SYMERRS);
        er32(MPC);
        er32(SCC);
        er32(ECOL);
        er32(MCC);
        er32(LATECOL);
        er32(COLC);
        er32(DC);
        er32(SEC);
        er32(RLEC);
        er32(XONRXC);
        er32(XONTXC);
        er32(XOFFRXC);
        er32(XOFFTXC);
        er32(FCRUC);
        er32(GPRC);
        er32(BPRC);
        er32(MPRC);
        er32(GPTC);
        er32(GORCL);
        er32(GORCH);
        er32(GOTCL);
        er32(GOTCH);
        er32(RNBC);
        er32(RUC);
        er32(RFC);
        er32(ROC);
        er32(RJC);
        er32(TORL);
        er32(TORH);
        er32(TOTL);
        er32(TOTH);
        er32(TPR);
        er32(TPT);
        er32(MPTC);
        er32(BPTC);
}

/**
 *  e1000e_check_for_copper_link - Check for link (Copper)
 *  @hw: pointer to the HW structure
 *
 *  Checks to see of the link status of the hardware has changed.  If a
 *  change in link status has been detected, then we read the PHY registers
 *  to get the current speed/duplex if link exists.
 **/
s32 e1000e_check_for_copper_link(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val;
        bool link;

        /* We only want to go out to the PHY registers to see if Auto-Neg
         * has completed and/or if our link status has changed.  The
         * get_link_status flag is set upon receiving a Link Status
         * Change or Rx Sequence Error interrupt.
         */
        if (!mac->get_link_status)
                return 0;

        /* First we want to see if the MII Status Register reports
         * link.  If so, then we want to get the current speed/duplex
         * of the PHY.
         */
        ret_val = e1000e_phy_has_link_generic(hw, 1, 0, &link);
        if (ret_val)
                return ret_val;

        if (!link)
                return 0;       /* No link detected */

        mac->get_link_status = false;

        /* Check if there was DownShift, must be checked
         * immediately after link-up
         */
        e1000e_check_downshift(hw);

        /* If we are forcing speed/duplex, then we simply return since
         * we have already determined whether we have link or not.
         */
        if (!mac->autoneg)
                return -E1000_ERR_CONFIG;

        /* Auto-Neg is enabled.  Auto Speed Detection takes care
         * of MAC speed/duplex configuration.  So we only need to
         * configure Collision Distance in the MAC.
         */
        mac->ops.config_collision_dist(hw);

        /* Configure Flow Control now that Auto-Neg has completed.
         * First, we need to restore the desired flow control
         * settings because we may have had to re-autoneg with a
         * different link partner.
         */
        ret_val = e1000e_config_fc_after_link_up(hw);
        if (ret_val)
                e_dbg("Error configuring flow control\n");

        return ret_val;
}

/**
 *  e1000e_check_for_fiber_link - Check for link (Fiber)
 *  @hw: pointer to the HW structure
 *
 *  Checks for link up on the hardware.  If link is not up and we have
 *  a signal, then we need to force link up.
 **/
s32 e1000e_check_for_fiber_link(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        u32 rxcw;
        u32 ctrl;
        u32 status;
        s32 ret_val;

        ctrl = er32(CTRL);
        status = er32(STATUS);
        rxcw = er32(RXCW);

        /* If we don't have link (auto-negotiation failed or link partner
         * cannot auto-negotiate), the cable is plugged in (we have signal),
         * and our link partner is not trying to auto-negotiate with us (we
         * are receiving idles or data), we need to force link up. We also
         * need to give auto-negotiation time to complete, in case the cable
         * was just plugged in. The autoneg_failed flag does this.
         */
        /* (ctrl & E1000_CTRL_SWDPIN1) == 1 == have signal */
        if ((ctrl & E1000_CTRL_SWDPIN1) && !(status & E1000_STATUS_LU) &&
            !(rxcw & E1000_RXCW_C)) {
                if (!mac->autoneg_failed) {
                        mac->autoneg_failed = true;
                        return 0;
                }
                e_dbg("NOT Rx'ing /C/, disable AutoNeg and force link.\n");

                /* Disable auto-negotiation in the TXCW register */
                ew32(TXCW, (mac->txcw & ~E1000_TXCW_ANE));

                /* Force link-up and also force full-duplex. */
                ctrl = er32(CTRL);
                ctrl |= (E1000_CTRL_SLU | E1000_CTRL_FD);
                ew32(CTRL, ctrl);

                /* Configure Flow Control after forcing link up. */
                ret_val = e1000e_config_fc_after_link_up(hw);
                if (ret_val) {
                        e_dbg("Error configuring flow control\n");
                        return ret_val;
                }
        } else if ((ctrl & E1000_CTRL_SLU) && (rxcw & E1000_RXCW_C)) {
                /* If we are forcing link and we are receiving /C/ ordered
                 * sets, re-enable auto-negotiation in the TXCW register
                 * and disable forced link in the Device Control register
                 * in an attempt to auto-negotiate with our link partner.
                 */
                e_dbg("Rx'ing /C/, enable AutoNeg and stop forcing link.\n");
                ew32(TXCW, mac->txcw);
                ew32(CTRL, (ctrl & ~E1000_CTRL_SLU));

                mac->serdes_has_link = true;
        }

        return 0;
}

/**
 *  e1000e_check_for_serdes_link - Check for link (Serdes)
 *  @hw: pointer to the HW structure
 *
 *  Checks for link up on the hardware.  If link is not up and we have
 *  a signal, then we need to force link up.
 **/
s32 e1000e_check_for_serdes_link(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        u32 rxcw;
        u32 ctrl;
        u32 status;
        s32 ret_val;

        ctrl = er32(CTRL);
        status = er32(STATUS);
        rxcw = er32(RXCW);

        /* If we don't have link (auto-negotiation failed or link partner
         * cannot auto-negotiate), and our link partner is not trying to
         * auto-negotiate with us (we are receiving idles or data),
         * we need to force link up. We also need to give auto-negotiation
         * time to complete.
         */
        /* (ctrl & E1000_CTRL_SWDPIN1) == 1 == have signal */
        if (!(status & E1000_STATUS_LU) && !(rxcw & E1000_RXCW_C)) {
                if (!mac->autoneg_failed) {
                        mac->autoneg_failed = true;
                        return 0;
                }
                e_dbg("NOT Rx'ing /C/, disable AutoNeg and force link.\n");

                /* Disable auto-negotiation in the TXCW register */
                ew32(TXCW, (mac->txcw & ~E1000_TXCW_ANE));

                /* Force link-up and also force full-duplex. */
                ctrl = er32(CTRL);
                ctrl |= (E1000_CTRL_SLU | E1000_CTRL_FD);
                ew32(CTRL, ctrl);

                /* Configure Flow Control after forcing link up. */
                ret_val = e1000e_config_fc_after_link_up(hw);
                if (ret_val) {
                        e_dbg("Error configuring flow control\n");
                        return ret_val;
                }
        } else if ((ctrl & E1000_CTRL_SLU) && (rxcw & E1000_RXCW_C)) {
                /* If we are forcing link and we are receiving /C/ ordered
                 * sets, re-enable auto-negotiation in the TXCW register
                 * and disable forced link in the Device Control register
                 * in an attempt to auto-negotiate with our link partner.
                 */
                e_dbg("Rx'ing /C/, enable AutoNeg and stop forcing link.\n");
                ew32(TXCW, mac->txcw);
                ew32(CTRL, (ctrl & ~E1000_CTRL_SLU));

                mac->serdes_has_link = true;
        } else if (!(E1000_TXCW_ANE & er32(TXCW))) {
                /* If we force link for non-auto-negotiation switch, check
                 * link status based on MAC synchronization for internal
                 * serdes media type.
                 */
                /* SYNCH bit and IV bit are sticky. */
                usleep_range(10, 20);
                rxcw = er32(RXCW);
                if (rxcw & E1000_RXCW_SYNCH) {
                        if (!(rxcw & E1000_RXCW_IV)) {
                                mac->serdes_has_link = true;
                                e_dbg("SERDES: Link up - forced.\n");
                        }
                } else {
                        mac->serdes_has_link = false;
                        e_dbg("SERDES: Link down - force failed.\n");
                }
        }

        if (E1000_TXCW_ANE & er32(TXCW)) {
                status = er32(STATUS);
                if (status & E1000_STATUS_LU) {
                        /* SYNCH bit and IV bit are sticky, so reread rxcw. */
                        usleep_range(10, 20);
                        rxcw = er32(RXCW);
                        if (rxcw & E1000_RXCW_SYNCH) {
                                if (!(rxcw & E1000_RXCW_IV)) {
                                        mac->serdes_has_link = true;
                                        e_dbg("SERDES: Link up - autoneg completed successfully.\n");
                                } else {
                                        mac->serdes_has_link = false;
                                        e_dbg("SERDES: Link down - invalid codewords detected in autoneg.\n");
                                }
                        } else {
                                mac->serdes_has_link = false;
                                e_dbg("SERDES: Link down - no sync.\n");
                        }
                } else {
                        mac->serdes_has_link = false;
                        e_dbg("SERDES: Link down - autoneg failed\n");
                }
        }

        return 0;
}

/**
 *  e1000_set_default_fc_generic - Set flow control default values
 *  @hw: pointer to the HW structure
 *
 *  Read the EEPROM for the default values for flow control and store the
 *  values.
 **/
static s32 e1000_set_default_fc_generic(struct e1000_hw *hw)
{
        s32 ret_val;
        u16 nvm_data;

        /* Read and store word 0x0F of the EEPROM. This word contains bits
         * that determine the hardware's default PAUSE (flow control) mode,
         * a bit that determines whether the HW defaults to enabling or
         * disabling auto-negotiation, and the direction of the
         * SW defined pins. If there is no SW over-ride of the flow
         * control setting, then the variable hw->fc will
         * be initialized based on a value in the EEPROM.
         */
        ret_val = e1000_read_nvm(hw, NVM_INIT_CONTROL2_REG, 1, &nvm_data);

        if (ret_val) {
                e_dbg("NVM Read Error\n");
                return ret_val;
        }

        if (!(nvm_data & NVM_WORD0F_PAUSE_MASK))
                hw->fc.requested_mode = e1000_fc_none;
        else if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == NVM_WORD0F_ASM_DIR)
                hw->fc.requested_mode = e1000_fc_tx_pause;
        else
                hw->fc.requested_mode = e1000_fc_full;

        return 0;
}

/**
 *  e1000e_setup_link_generic - Setup flow control and link settings
 *  @hw: pointer to the HW structure
 *
 *  Determines which flow control settings to use, then configures flow
 *  control.  Calls the appropriate media-specific link configuration
 *  function.  Assuming the adapter has a valid link partner, a valid link
 *  should be established.  Assumes the hardware has previously been reset
 *  and the transmitter and receiver are not enabled.
 **/
s32 e1000e_setup_link_generic(struct e1000_hw *hw)
{
        s32 ret_val;

        /* In the case of the phy reset being blocked, we already have a link.
         * We do not need to set it up again.
         */
        if (hw->phy.ops.check_reset_block && hw->phy.ops.check_reset_block(hw))
                return 0;

        /* If requested flow control is set to default, set flow control
         * based on the EEPROM flow control settings.
         */
        if (hw->fc.requested_mode == e1000_fc_default) {
                ret_val = e1000_set_default_fc_generic(hw);
                if (ret_val)
                        return ret_val;
        }

        /* Save off the requested flow control mode for use later.  Depending
         * on the link partner's capabilities, we may or may not use this mode.
         */
        hw->fc.current_mode = hw->fc.requested_mode;

        e_dbg("After fix-ups FlowControl is now = %x\n", hw->fc.current_mode);

        /* Call the necessary media_type subroutine to configure the link. */
        ret_val = hw->mac.ops.setup_physical_interface(hw);
        if (ret_val)
                return ret_val;

        /* Initialize the flow control address, type, and PAUSE timer
         * registers to their default values.  This is done even if flow
         * control is disabled, because it does not hurt anything to
         * initialize these registers.
         */
        e_dbg("Initializing the Flow Control address, type and timer regs\n");
        ew32(FCT, FLOW_CONTROL_TYPE);
        ew32(FCAH, FLOW_CONTROL_ADDRESS_HIGH);
        ew32(FCAL, FLOW_CONTROL_ADDRESS_LOW);

        ew32(FCTTV, hw->fc.pause_time);

        return e1000e_set_fc_watermarks(hw);
}

/**
 *  e1000_commit_fc_settings_generic - Configure flow control
 *  @hw: pointer to the HW structure
 *
 *  Write the flow control settings to the Transmit Config Word Register (TXCW)
 *  base on the flow control settings in e1000_mac_info.
 **/
static s32 e1000_commit_fc_settings_generic(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        u32 txcw;

        /* Check for a software override of the flow control settings, and
         * setup the device accordingly.  If auto-negotiation is enabled, then
         * software will have to set the "PAUSE" bits to the correct value in
         * the Transmit Config Word Register (TXCW) and re-start auto-
         * negotiation.  However, if auto-negotiation is disabled, then
         * software will have to manually configure the two flow control enable
         * bits in the CTRL register.
         *
         * The possible values of the "fc" parameter are:
         *      0:  Flow control is completely disabled
         *      1:  Rx flow control is enabled (we can receive pause frames,
         *          but not send pause frames).
         *      2:  Tx flow control is enabled (we can send pause frames but we
         *          do not support receiving pause frames).
         *      3:  Both Rx and Tx flow control (symmetric) are enabled.
         */
        switch (hw->fc.current_mode) {
        case e1000_fc_none:
                /* Flow control completely disabled by a software over-ride. */
                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD);
                break;
        case e1000_fc_rx_pause:
                /* Rx Flow control is enabled and Tx Flow control is disabled
                 * by a software over-ride. Since there really isn't a way to
                 * advertise that we are capable of Rx Pause ONLY, we will
                 * advertise that we support both symmetric and asymmetric Rx
                 * PAUSE.  Later, we will disable the adapter's ability to send
                 * PAUSE frames.
                 */
                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
                break;
        case e1000_fc_tx_pause:
                /* Tx Flow control is enabled, and Rx Flow control is disabled,
                 * by a software over-ride.
                 */
                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_ASM_DIR);
                break;
        case e1000_fc_full:
                /* Flow control (both Rx and Tx) is enabled by a software
                 * over-ride.
                 */
                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
                break;
        default:
                e_dbg("Flow control param set incorrectly\n");
                return -E1000_ERR_CONFIG;
                break;
        }

        ew32(TXCW, txcw);
        mac->txcw = txcw;

        return 0;
}

/**
 *  e1000_poll_fiber_serdes_link_generic - Poll for link up
 *  @hw: pointer to the HW structure
 *
 *  Polls for link up by reading the status register, if link fails to come
 *  up with auto-negotiation, then the link is forced if a signal is detected.
 **/
static s32 e1000_poll_fiber_serdes_link_generic(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        u32 i, status;
        s32 ret_val;

        /* If we have a signal (the cable is plugged in, or assumed true for
         * serdes media) then poll for a "Link-Up" indication in the Device
         * Status Register.  Time-out if a link isn't seen in 500 milliseconds
         * seconds (Auto-negotiation should complete in less than 500
         * milliseconds even if the other end is doing it in SW).
         */
        for (i = 0; i < FIBER_LINK_UP_LIMIT; i++) {
                usleep_range(10000, 20000);
                status = er32(STATUS);
                if (status & E1000_STATUS_LU)
                        break;
        }
        if (i == FIBER_LINK_UP_LIMIT) {
                e_dbg("Never got a valid link from auto-neg!!!\n");
                mac->autoneg_failed = true;
                /* AutoNeg failed to achieve a link, so we'll call
                 * mac->check_for_link. This routine will force the
                 * link up if we detect a signal. This will allow us to
                 * communicate with non-autonegotiating link partners.
                 */
                ret_val = mac->ops.check_for_link(hw);
                if (ret_val) {
                        e_dbg("Error while checking for link\n");
                        return ret_val;
                }
                mac->autoneg_failed = false;
        } else {
                mac->autoneg_failed = false;
                e_dbg("Valid Link Found\n");
        }

        return 0;
}

/**
 *  e1000e_setup_fiber_serdes_link - Setup link for fiber/serdes
 *  @hw: pointer to the HW structure
 *
 *  Configures collision distance and flow control for fiber and serdes
 *  links.  Upon successful setup, poll for link.
 **/
s32 e1000e_setup_fiber_serdes_link(struct e1000_hw *hw)
{
        u32 ctrl;
        s32 ret_val;

        ctrl = er32(CTRL);

        /* Take the link out of reset */
        ctrl &= ~E1000_CTRL_LRST;

        hw->mac.ops.config_collision_dist(hw);

        ret_val = e1000_commit_fc_settings_generic(hw);
        if (ret_val)
                return ret_val;

        /* Since auto-negotiation is enabled, take the link out of reset (the
         * link will be in reset, because we previously reset the chip). This
         * will restart auto-negotiation.  If auto-negotiation is successful
         * then the link-up status bit will be set and the flow control enable
         * bits (RFCE and TFCE) will be set according to their negotiated value.
         */
        e_dbg("Auto-negotiation enabled\n");

        ew32(CTRL, ctrl);
        e1e_flush();
        usleep_range(1000, 2000);

        /* For these adapters, the SW definable pin 1 is set when the optics
         * detect a signal.  If we have a signal, then poll for a "Link-Up"
         * indication.
         */
        if (hw->phy.media_type == e1000_media_type_internal_serdes ||
            (er32(CTRL) & E1000_CTRL_SWDPIN1)) {
                ret_val = e1000_poll_fiber_serdes_link_generic(hw);
        } else {
                e_dbg("No signal detected\n");
        }

        return ret_val;
}

/**
 *  e1000e_config_collision_dist_generic - Configure collision distance
 *  @hw: pointer to the HW structure
 *
 *  Configures the collision distance to the default value and is used
 *  during link setup.
 **/
void e1000e_config_collision_dist_generic(struct e1000_hw *hw)
{
        u32 tctl;

        tctl = er32(TCTL);

        tctl &= ~E1000_TCTL_COLD;
        tctl |= E1000_COLLISION_DISTANCE << E1000_COLD_SHIFT;

        ew32(TCTL, tctl);
        e1e_flush();
}

/**
 *  e1000e_set_fc_watermarks - Set flow control high/low watermarks
 *  @hw: pointer to the HW structure
 *
 *  Sets the flow control high/low threshold (watermark) registers.  If
 *  flow control XON frame transmission is enabled, then set XON frame
 *  transmission as well.
 **/
s32 e1000e_set_fc_watermarks(struct e1000_hw *hw)
{
        u32 fcrtl = 0, fcrth = 0;

        /* Set the flow control receive threshold registers.  Normally,
         * these registers will be set to a default threshold that may be
         * adjusted later by the driver's runtime code.  However, if the
         * ability to transmit pause frames is not enabled, then these
         * registers will be set to 0.
         */
        if (hw->fc.current_mode & e1000_fc_tx_pause) {
                /* We need to set up the Receive Threshold high and low water
                 * marks as well as (optionally) enabling the transmission of
                 * XON frames.
                 */
                fcrtl = hw->fc.low_water;
                if (hw->fc.send_xon)
                        fcrtl |= E1000_FCRTL_XONE;

                fcrth = hw->fc.high_water;
        }
        ew32(FCRTL, fcrtl);
        ew32(FCRTH, fcrth);

        return 0;
}

/**
 *  e1000e_force_mac_fc - Force the MAC's flow control settings
 *  @hw: pointer to the HW structure
 *
 *  Force the MAC's flow control settings.  Sets the TFCE and RFCE bits in the
 *  device control register to reflect the adapter settings.  TFCE and RFCE
 *  need to be explicitly set by software when a copper PHY is used because
 *  autonegotiation is managed by the PHY rather than the MAC.  Software must
 *  also configure these bits when link is forced on a fiber connection.
 **/
s32 e1000e_force_mac_fc(struct e1000_hw *hw)
{
        u32 ctrl;

        ctrl = er32(CTRL);

        /* Because we didn't get link via the internal auto-negotiation
         * mechanism (we either forced link or we got link via PHY
         * auto-neg), we have to manually enable/disable transmit an
         * receive flow control.
         *
         * The "Case" statement below enables/disable flow control
         * according to the "hw->fc.current_mode" parameter.
         *
         * The possible values of the "fc" parameter are:
         *      0:  Flow control is completely disabled
         *      1:  Rx flow control is enabled (we can receive pause
         *          frames but not send pause frames).
         *      2:  Tx flow control is enabled (we can send pause frames
         *          frames but we do not receive pause frames).
         *      3:  Both Rx and Tx flow control (symmetric) is enabled.
         *  other:  No other values should be possible at this point.
         */
        e_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);

        switch (hw->fc.current_mode) {
        case e1000_fc_none:
                ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
                break;
        case e1000_fc_rx_pause:
                ctrl &= (~E1000_CTRL_TFCE);
                ctrl |= E1000_CTRL_RFCE;
                break;
        case e1000_fc_tx_pause:
                ctrl &= (~E1000_CTRL_RFCE);
                ctrl |= E1000_CTRL_TFCE;
                break;
        case e1000_fc_full:
                ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
                break;
        default:
                e_dbg("Flow control param set incorrectly\n");
                return -E1000_ERR_CONFIG;
        }

        ew32(CTRL, ctrl);

        return 0;
}

/**
 *  e1000e_config_fc_after_link_up - Configures flow control after link
 *  @hw: pointer to the HW structure
 *
 *  Checks the status of auto-negotiation after link up to ensure that the
 *  speed and duplex were not forced.  If the link needed to be forced, then
 *  flow control needs to be forced also.  If auto-negotiation is enabled
 *  and did not fail, then we configure flow control based on our link
 *  partner.
 **/
s32 e1000e_config_fc_after_link_up(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val = 0;
        u32 pcs_status_reg, pcs_adv_reg, pcs_lp_ability_reg, pcs_ctrl_reg;
        u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
        u16 speed, duplex;

        /* Check for the case where we have fiber media and auto-neg failed
         * so we had to force link.  In this case, we need to force the
         * configuration of the MAC to match the "fc" parameter.
         */
        if (mac->autoneg_failed) {
                if (hw->phy.media_type == e1000_media_type_fiber ||
                    hw->phy.media_type == e1000_media_type_internal_serdes)
                        ret_val = e1000e_force_mac_fc(hw);
        } else {
                if (hw->phy.media_type == e1000_media_type_copper)
                        ret_val = e1000e_force_mac_fc(hw);
        }

        if (ret_val) {
                e_dbg("Error forcing flow control settings\n");
                return ret_val;
        }

        /* Check for the case where we have copper media and auto-neg is
         * enabled.  In this case, we need to check and see if Auto-Neg
         * has completed, and if so, how the PHY and link partner has
         * flow control configured.
         */
        if ((hw->phy.media_type == e1000_media_type_copper) && mac->autoneg) {
                /* Read the MII Status Register and check to see if AutoNeg
                 * has completed.  We read this twice because this reg has
                 * some "sticky" (latched) bits.
                 */
                ret_val = e1e_rphy(hw, MII_BMSR, &mii_status_reg);
                if (ret_val)
                        return ret_val;
                ret_val = e1e_rphy(hw, MII_BMSR, &mii_status_reg);
                if (ret_val)
                        return ret_val;

                if (!(mii_status_reg & BMSR_ANEGCOMPLETE)) {
                        e_dbg("Copper PHY and Auto Neg has not completed.\n");
                        return ret_val;
                }

                /* The AutoNeg process has completed, so we now need to
                 * read both the Auto Negotiation Advertisement
                 * Register (Address 4) and the Auto_Negotiation Base
                 * Page Ability Register (Address 5) to determine how
                 * flow control was negotiated.
                 */
                ret_val = e1e_rphy(hw, MII_ADVERTISE, &mii_nway_adv_reg);
                if (ret_val)
                        return ret_val;
                ret_val = e1e_rphy(hw, MII_LPA, &mii_nway_lp_ability_reg);
                if (ret_val)
                        return ret_val;

                /* Two bits in the Auto Negotiation Advertisement Register
                 * (Address 4) and two bits in the Auto Negotiation Base
                 * Page Ability Register (Address 5) determine flow control
                 * for both the PHY and the link partner.  The following
                 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
                 * 1999, describes these PAUSE resolution bits and how flow
                 * control is determined based upon these settings.
                 * NOTE:  DC = Don't Care
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
                 *-------|---------|-------|---------|--------------------
                 *   0   |    0    |  DC   |   DC    | e1000_fc_none
                 *   0   |    1    |   0   |   DC    | e1000_fc_none
                 *   0   |    1    |   1   |    0    | e1000_fc_none
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 *   1   |    0    |   0   |   DC    | e1000_fc_none
                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
                 *   1   |    1    |   0   |    0    | e1000_fc_none
                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
                 *
                 * Are both PAUSE bits set to 1?  If so, this implies
                 * Symmetric Flow Control is enabled at both ends.  The
                 * ASM_DIR bits are irrelevant per the spec.
                 *
                 * For Symmetric Flow Control:
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |   DC    |   1   |   DC    | E1000_fc_full
                 *
                 */
                if ((mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
                    (mii_nway_lp_ability_reg & LPA_PAUSE_CAP)) {
                        /* Now we need to check if the user selected Rx ONLY
                         * of pause frames.  In this case, we had to advertise
                         * FULL flow control because we could not advertise Rx
                         * ONLY. Hence, we must now check to see if we need to
                         * turn OFF the TRANSMISSION of PAUSE frames.
                         */
                        if (hw->fc.requested_mode == e1000_fc_full) {
                                hw->fc.current_mode = e1000_fc_full;
                                e_dbg("Flow Control = FULL.\n");
                        } else {
                                hw->fc.current_mode = e1000_fc_rx_pause;
                                e_dbg("Flow Control = Rx PAUSE frames only.\n");
                        }
                }
                /* For receiving PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 */
                else if (!(mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
                         (mii_nway_adv_reg & ADVERTISE_PAUSE_ASYM) &&
                         (mii_nway_lp_ability_reg & LPA_PAUSE_CAP) &&
                         (mii_nway_lp_ability_reg & LPA_PAUSE_ASYM)) {
                        hw->fc.current_mode = e1000_fc_tx_pause;
                        e_dbg("Flow Control = Tx PAUSE frames only.\n");
                }
                /* For transmitting PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
                 */
                else if ((mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
                         (mii_nway_adv_reg & ADVERTISE_PAUSE_ASYM) &&
                         !(mii_nway_lp_ability_reg & LPA_PAUSE_CAP) &&
                         (mii_nway_lp_ability_reg & LPA_PAUSE_ASYM)) {
                        hw->fc.current_mode = e1000_fc_rx_pause;
                        e_dbg("Flow Control = Rx PAUSE frames only.\n");
                } else {
                        /* Per the IEEE spec, at this point flow control
                         * should be disabled.
                         */
                        hw->fc.current_mode = e1000_fc_none;
                        e_dbg("Flow Control = NONE.\n");
                }

                /* Now we need to do one last check...  If we auto-
                 * negotiated to HALF DUPLEX, flow control should not be
                 * enabled per IEEE 802.3 spec.
                 */
                ret_val = mac->ops.get_link_up_info(hw, &speed, &duplex);
                if (ret_val) {
                        e_dbg("Error getting link speed and duplex\n");
                        return ret_val;
                }

                if (duplex == HALF_DUPLEX)
                        hw->fc.current_mode = e1000_fc_none;

                /* Now we call a subroutine to actually force the MAC
                 * controller to use the correct flow control settings.
                 */
                ret_val = e1000e_force_mac_fc(hw);
                if (ret_val) {
                        e_dbg("Error forcing flow control settings\n");
                        return ret_val;
                }
        }

        /* Check for the case where we have SerDes media and auto-neg is
         * enabled.  In this case, we need to check and see if Auto-Neg
         * has completed, and if so, how the PHY and link partner has
         * flow control configured.
         */
        if ((hw->phy.media_type == e1000_media_type_internal_serdes) &&
            mac->autoneg) {
                /* Read the PCS_LSTS and check to see if AutoNeg
                 * has completed.
                 */
                pcs_status_reg = er32(PCS_LSTAT);

                if (!(pcs_status_reg & E1000_PCS_LSTS_AN_COMPLETE)) {
                        e_dbg("PCS Auto Neg has not completed.\n");
                        return ret_val;
                }

                /* The AutoNeg process has completed, so we now need to
                 * read both the Auto Negotiation Advertisement
                 * Register (PCS_ANADV) and the Auto_Negotiation Base
                 * Page Ability Register (PCS_LPAB) to determine how
                 * flow control was negotiated.
                 */
                pcs_adv_reg = er32(PCS_ANADV);
                pcs_lp_ability_reg = er32(PCS_LPAB);

                /* Two bits in the Auto Negotiation Advertisement Register
                 * (PCS_ANADV) and two bits in the Auto Negotiation Base
                 * Page Ability Register (PCS_LPAB) determine flow control
                 * for both the PHY and the link partner.  The following
                 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
                 * 1999, describes these PAUSE resolution bits and how flow
                 * control is determined based upon these settings.
                 * NOTE:  DC = Don't Care
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
                 *-------|---------|-------|---------|--------------------
                 *   0   |    0    |  DC   |   DC    | e1000_fc_none
                 *   0   |    1    |   0   |   DC    | e1000_fc_none
                 *   0   |    1    |   1   |    0    | e1000_fc_none
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 *   1   |    0    |   0   |   DC    | e1000_fc_none
                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
                 *   1   |    1    |   0   |    0    | e1000_fc_none
                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
                 *
                 * Are both PAUSE bits set to 1?  If so, this implies
                 * Symmetric Flow Control is enabled at both ends.  The
                 * ASM_DIR bits are irrelevant per the spec.
                 *
                 * For Symmetric Flow Control:
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
                 *
                 */
                if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
                    (pcs_lp_ability_reg & E1000_TXCW_PAUSE)) {
                        /* Now we need to check if the user selected Rx ONLY
                         * of pause frames.  In this case, we had to advertise
                         * FULL flow control because we could not advertise Rx
                         * ONLY. Hence, we must now check to see if we need to
                         * turn OFF the TRANSMISSION of PAUSE frames.
                         */
                        if (hw->fc.requested_mode == e1000_fc_full) {
                                hw->fc.current_mode = e1000_fc_full;
                                e_dbg("Flow Control = FULL.\n");
                        } else {
                                hw->fc.current_mode = e1000_fc_rx_pause;
                                e_dbg("Flow Control = Rx PAUSE frames only.\n");
                        }
                }
                /* For receiving PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 */
                else if (!(pcs_adv_reg & E1000_TXCW_PAUSE) &&
                         (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
                         (pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
                         (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
                        hw->fc.current_mode = e1000_fc_tx_pause;
                        e_dbg("Flow Control = Tx PAUSE frames only.\n");
                }
                /* For transmitting PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
                 */
                else if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
                         (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
                         !(pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
                         (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
                        hw->fc.current_mode = e1000_fc_rx_pause;
                        e_dbg("Flow Control = Rx PAUSE frames only.\n");
                } else {
                        /* Per the IEEE spec, at this point flow control
                         * should be disabled.
                         */
                        hw->fc.current_mode = e1000_fc_none;
                        e_dbg("Flow Control = NONE.\n");
                }

                /* Now we call a subroutine to actually force the MAC
                 * controller to use the correct flow control settings.
                 */
                pcs_ctrl_reg = er32(PCS_LCTL);
                pcs_ctrl_reg |= E1000_PCS_LCTL_FORCE_FCTRL;
                ew32(PCS_LCTL, pcs_ctrl_reg);

                ret_val = e1000e_force_mac_fc(hw);
                if (ret_val) {
                        e_dbg("Error forcing flow control settings\n");
                        return ret_val;
                }
        }

        return 0;
}

/**
 *  e1000e_get_speed_and_duplex_copper - Retrieve current speed/duplex
 *  @hw: pointer to the HW structure
 *  @speed: stores the current speed
 *  @duplex: stores the current duplex
 *
 *  Read the status register for the current speed/duplex and store the current
 *  speed and duplex for copper connections.
 **/
s32 e1000e_get_speed_and_duplex_copper(struct e1000_hw *hw, u16 *speed,
                                       u16 *duplex)
{
        u32 status;

        status = er32(STATUS);
        if (status & E1000_STATUS_SPEED_1000)
                *speed = SPEED_1000;
        else if (status & E1000_STATUS_SPEED_100)
                *speed = SPEED_100;
        else
                *speed = SPEED_10;

        if (status & E1000_STATUS_FD)
                *duplex = FULL_DUPLEX;
        else
                *duplex = HALF_DUPLEX;

        e_dbg("%u Mbps, %s Duplex\n",
              *speed == SPEED_1000 ? 1000 : *speed == SPEED_100 ? 100 : 10,
              *duplex == FULL_DUPLEX ? "Full" : "Half");

        return 0;
}

/**
 *  e1000e_get_speed_and_duplex_fiber_serdes - Retrieve current speed/duplex
 *  @hw: pointer to the HW structure
 *  @speed: stores the current speed
 *  @duplex: stores the current duplex
 *
 *  Sets the speed and duplex to gigabit full duplex (the only possible option)
 *  for fiber/serdes links.
 **/
s32 e1000e_get_speed_and_duplex_fiber_serdes(struct e1000_hw __always_unused
                                             *hw, u16 *speed, u16 *duplex)
{
        *speed = SPEED_1000;
        *duplex = FULL_DUPLEX;

        return 0;
}

/**
 *  e1000e_get_hw_semaphore - Acquire hardware semaphore
 *  @hw: pointer to the HW structure
 *
 *  Acquire the HW semaphore to access the PHY or NVM
 **/
s32 e1000e_get_hw_semaphore(struct e1000_hw *hw)
{
        u32 swsm;
        s32 timeout = hw->nvm.word_size + 1;
        s32 i = 0;

        /* Get the SW semaphore */
        while (i < timeout) {
                swsm = er32(SWSM);
                if (!(swsm & E1000_SWSM_SMBI))
                        break;

                usleep_range(50, 100);
                i++;
        }

        if (i == timeout) {
                e_dbg("Driver can't access device - SMBI bit is set.\n");
                return -E1000_ERR_NVM;
        }

        /* Get the FW semaphore. */
        for (i = 0; i < timeout; i++) {
                swsm = er32(SWSM);
                ew32(SWSM, swsm | E1000_SWSM_SWESMBI);

                /* Semaphore acquired if bit latched */
                if (er32(SWSM) & E1000_SWSM_SWESMBI)
                        break;

                usleep_range(50, 100);
        }

        if (i == timeout) {
                /* Release semaphores */
                e1000e_put_hw_semaphore(hw);
                e_dbg("Driver can't access the NVM\n");
                return -E1000_ERR_NVM;
        }

        return 0;
}

/**
 *  e1000e_put_hw_semaphore - Release hardware semaphore
 *  @hw: pointer to the HW structure
 *
 *  Release hardware semaphore used to access the PHY or NVM
 **/
void e1000e_put_hw_semaphore(struct e1000_hw *hw)
{
        u32 swsm;

        swsm = er32(SWSM);
        swsm &= ~(E1000_SWSM_SMBI | E1000_SWSM_SWESMBI);
        ew32(SWSM, swsm);
}

/**
 *  e1000e_get_auto_rd_done - Check for auto read completion
 *  @hw: pointer to the HW structure
 *
 *  Check EEPROM for Auto Read done bit.
 **/
s32 e1000e_get_auto_rd_done(struct e1000_hw *hw)
{
        s32 i = 0;

        while (i < AUTO_READ_DONE_TIMEOUT) {
                if (er32(EECD) & E1000_EECD_AUTO_RD)
                        break;
                usleep_range(1000, 2000);
                i++;
        }

        if (i == AUTO_READ_DONE_TIMEOUT) {
                e_dbg("Auto read by HW from NVM has not completed.\n");
                return -E1000_ERR_RESET;
        }

        return 0;
}

/**
 *  e1000e_valid_led_default - Verify a valid default LED config
 *  @hw: pointer to the HW structure
 *  @data: pointer to the NVM (EEPROM)
 *
 *  Read the EEPROM for the current default LED configuration.  If the
 *  LED configuration is not valid, set to a valid LED configuration.
 **/
s32 e1000e_valid_led_default(struct e1000_hw *hw, u16 *data)
{
        s32 ret_val;

        ret_val = e1000_read_nvm(hw, NVM_ID_LED_SETTINGS, 1, data);
        if (ret_val) {
                e_dbg("NVM Read Error\n");
                return ret_val;
        }

        if (*data == ID_LED_RESERVED_0000 || *data == ID_LED_RESERVED_FFFF)
                *data = ID_LED_DEFAULT;

        return 0;
}

/**
 *  e1000e_id_led_init_generic -
 *  @hw: pointer to the HW structure
 *
 **/
s32 e1000e_id_led_init_generic(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val;
        const u32 ledctl_mask = 0x000000FF;
        const u32 ledctl_on = E1000_LEDCTL_MODE_LED_ON;
        const u32 ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
        u16 data, i, temp;
        const u16 led_mask = 0x0F;

        ret_val = hw->nvm.ops.valid_led_default(hw, &data);
        if (ret_val)
                return ret_val;

        mac->ledctl_default = er32(LEDCTL);
        mac->ledctl_mode1 = mac->ledctl_default;
        mac->ledctl_mode2 = mac->ledctl_default;

        for (i = 0; i < 4; i++) {
                temp = (data >> (i << 2)) & led_mask;
                switch (temp) {
                case ID_LED_ON1_DEF2:
                case ID_LED_ON1_ON2:
                case ID_LED_ON1_OFF2:
                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode1 |= ledctl_on << (i << 3);
                        break;
                case ID_LED_OFF1_DEF2:
                case ID_LED_OFF1_ON2:
                case ID_LED_OFF1_OFF2:
                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode1 |= ledctl_off << (i << 3);
                        break;
                default:
                        /* Do nothing */
                        break;
                }
                switch (temp) {
                case ID_LED_DEF1_ON2:
                case ID_LED_ON1_ON2:
                case ID_LED_OFF1_ON2:
                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode2 |= ledctl_on << (i << 3);
                        break;
                case ID_LED_DEF1_OFF2:
                case ID_LED_ON1_OFF2:
                case ID_LED_OFF1_OFF2:
                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode2 |= ledctl_off << (i << 3);
                        break;
                default:
                        /* Do nothing */
                        break;
                }
        }

        return 0;
}

/**
 *  e1000e_setup_led_generic - Configures SW controllable LED
 *  @hw: pointer to the HW structure
 *
 *  This prepares the SW controllable LED for use and saves the current state
 *  of the LED so it can be later restored.
 **/
s32 e1000e_setup_led_generic(struct e1000_hw *hw)
{
        u32 ledctl;

        if (hw->mac.ops.setup_led != e1000e_setup_led_generic)
                return -E1000_ERR_CONFIG;

        if (hw->phy.media_type == e1000_media_type_fiber) {
                ledctl = er32(LEDCTL);
                hw->mac.ledctl_default = ledctl;
                /* Turn off LED0 */
                ledctl &= ~(E1000_LEDCTL_LED0_IVRT | E1000_LEDCTL_LED0_BLINK |
                            E1000_LEDCTL_LED0_MODE_MASK);
                ledctl |= (E1000_LEDCTL_MODE_LED_OFF <<
                           E1000_LEDCTL_LED0_MODE_SHIFT);
                ew32(LEDCTL, ledctl);
        } else if (hw->phy.media_type == e1000_media_type_copper) {
                ew32(LEDCTL, hw->mac.ledctl_mode1);
        }

        return 0;
}

/**
 *  e1000e_cleanup_led_generic - Set LED config to default operation
 *  @hw: pointer to the HW structure
 *
 *  Remove the current LED configuration and set the LED configuration
 *  to the default value, saved from the EEPROM.
 **/
s32 e1000e_cleanup_led_generic(struct e1000_hw *hw)
{
        ew32(LEDCTL, hw->mac.ledctl_default);
        return 0;
}

/**
 *  e1000e_blink_led_generic - Blink LED
 *  @hw: pointer to the HW structure
 *
 *  Blink the LEDs which are set to be on.
 **/
s32 e1000e_blink_led_generic(struct e1000_hw *hw)
{
        u32 ledctl_blink = 0;
        u32 i;

        if (hw->phy.media_type == e1000_media_type_fiber) {
                /* always blink LED0 for PCI-E fiber */
                ledctl_blink = E1000_LEDCTL_LED0_BLINK |
                    (E1000_LEDCTL_MODE_LED_ON << E1000_LEDCTL_LED0_MODE_SHIFT);
        } else {
                /* Set the blink bit for each LED that's "on" (0x0E)
                 * (or "off" if inverted) in ledctl_mode2.  The blink
                 * logic in hardware only works when mode is set to "on"
                 * so it must be changed accordingly when the mode is
                 * "off" and inverted.
                 */
                ledctl_blink = hw->mac.ledctl_mode2;
                for (i = 0; i < 32; i += 8) {
                        u32 mode = (hw->mac.ledctl_mode2 >> i) &
                            E1000_LEDCTL_LED0_MODE_MASK;
                        u32 led_default = hw->mac.ledctl_default >> i;

                        if ((!(led_default & E1000_LEDCTL_LED0_IVRT) &&
                             (mode == E1000_LEDCTL_MODE_LED_ON)) ||
                            ((led_default & E1000_LEDCTL_LED0_IVRT) &&
                             (mode == E1000_LEDCTL_MODE_LED_OFF))) {
                                ledctl_blink &=
                                    ~(E1000_LEDCTL_LED0_MODE_MASK << i);
                                ledctl_blink |= (E1000_LEDCTL_LED0_BLINK |
                                                 E1000_LEDCTL_MODE_LED_ON) << i;
                        }
                }
        }

        ew32(LEDCTL, ledctl_blink);

        return 0;
}

/**
 *  e1000e_led_on_generic - Turn LED on
 *  @hw: pointer to the HW structure
 *
 *  Turn LED on.
 **/
s32 e1000e_led_on_generic(struct e1000_hw *hw)
{
        u32 ctrl;

        switch (hw->phy.media_type) {
        case e1000_media_type_fiber:
                ctrl = er32(CTRL);
                ctrl &= ~E1000_CTRL_SWDPIN0;
                ctrl |= E1000_CTRL_SWDPIO0;
                ew32(CTRL, ctrl);
                break;
        case e1000_media_type_copper:
                ew32(LEDCTL, hw->mac.ledctl_mode2);
                break;
        default:
                break;
        }

        return 0;
}

/**
 *  e1000e_led_off_generic - Turn LED off
 *  @hw: pointer to the HW structure
 *
 *  Turn LED off.
 **/
s32 e1000e_led_off_generic(struct e1000_hw *hw)
{
        u32 ctrl;

        switch (hw->phy.media_type) {
        case e1000_media_type_fiber:
                ctrl = er32(CTRL);
                ctrl |= E1000_CTRL_SWDPIN0;
                ctrl |= E1000_CTRL_SWDPIO0;
                ew32(CTRL, ctrl);
                break;
        case e1000_media_type_copper:
                ew32(LEDCTL, hw->mac.ledctl_mode1);
                break;
        default:
                break;
        }

        return 0;
}

/**
 *  e1000e_set_pcie_no_snoop - Set PCI-express capabilities
 *  @hw: pointer to the HW structure
 *  @no_snoop: bitmap of snoop events
 *
 *  Set the PCI-express register to snoop for events enabled in 'no_snoop'.
 **/
void e1000e_set_pcie_no_snoop(struct e1000_hw *hw, u32 no_snoop)
{
        u32 gcr;

        if (no_snoop) {
                gcr = er32(GCR);
                gcr &= ~(PCIE_NO_SNOOP_ALL);
                gcr |= no_snoop;
                ew32(GCR, gcr);
        }
}

/**
 *  e1000e_disable_pcie_master - Disables PCI-express master access
 *  @hw: pointer to the HW structure
 *
 *  Returns 0 if successful, else returns -10
 *  (-E1000_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
 *  the master requests to be disabled.
 *
 *  Disables PCI-Express master access and verifies there are no pending
 *  requests.
 **/
s32 e1000e_disable_pcie_master(struct e1000_hw *hw)
{
        u32 ctrl;
        s32 timeout = MASTER_DISABLE_TIMEOUT;

        ctrl = er32(CTRL);
        ctrl |= E1000_CTRL_GIO_MASTER_DISABLE;
        ew32(CTRL, ctrl);

        while (timeout) {
                if (!(er32(STATUS) & E1000_STATUS_GIO_MASTER_ENABLE))
                        break;
                usleep_range(100, 200);
                timeout--;
        }

        if (!timeout) {
                e_dbg("Master requests are pending.\n");
                return -E1000_ERR_MASTER_REQUESTS_PENDING;
        }

        return 0;
}

/**
 *  e1000e_reset_adaptive - Reset Adaptive Interframe Spacing
 *  @hw: pointer to the HW structure
 *
 *  Reset the Adaptive Interframe Spacing throttle to default values.
 **/
void e1000e_reset_adaptive(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;

        if (!mac->adaptive_ifs) {
                e_dbg("Not in Adaptive IFS mode!\n");
                return;
        }

        mac->current_ifs_val = 0;
        mac->ifs_min_val = IFS_MIN;
        mac->ifs_max_val = IFS_MAX;
        mac->ifs_step_size = IFS_STEP;
        mac->ifs_ratio = IFS_RATIO;

        mac->in_ifs_mode = false;
        ew32(AIT, 0);
}

/**
 *  e1000e_update_adaptive - Update Adaptive Interframe Spacing
 *  @hw: pointer to the HW structure
 *
 *  Update the Adaptive Interframe Spacing Throttle value based on the
 *  time between transmitted packets and time between collisions.
 **/
void e1000e_update_adaptive(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;

        if (!mac->adaptive_ifs) {
                e_dbg("Not in Adaptive IFS mode!\n");
                return;
        }

        if ((mac->collision_delta * mac->ifs_ratio) > mac->tx_packet_delta) {
                if (mac->tx_packet_delta > MIN_NUM_XMITS) {
                        mac->in_ifs_mode = true;
                        if (mac->current_ifs_val < mac->ifs_max_val) {
                                if (!mac->current_ifs_val)
                                        mac->current_ifs_val = mac->ifs_min_val;
                                else
                                        mac->current_ifs_val +=
                                            mac->ifs_step_size;
                                ew32(AIT, mac->current_ifs_val);
                        }
                }
        } else {
                if (mac->in_ifs_mode &&
                    (mac->tx_packet_delta <= MIN_NUM_XMITS)) {
                        mac->current_ifs_val = 0;
                        mac->in_ifs_mode = false;
                        ew32(AIT, 0);
                }
        }
}